Touch display apparatus, driving circuit, and driving method

ABSTRACT

A touch display apparatus, a corresponding driving circuit, and a driving method. The touch display apparatus includes a common electrode between a first substrate and a second substrate, and a driving circuit used as a touch sensing electrode during a touch sensing phase. The driving circuit is used for providing a first signal for touch detection to the common electrode. The driving circuit is also used for providing a second signal to a gate line during the touch sensing phase, said second signal enabling a thin-film transistor to be in off mode and decreasing the charge-discharge capacity of a capacitor formed by the common electrode and a gate line. The driving circuit is also used for providing a third signal during the touch sensing phase, the third signal decreasing the charge-discharge capacity of a capacitor formed by the common electrode and a data line.

The present application is the national phase of InternationalApplication No. PCT/CN2014/072080, titled “TOUCH DISPLAY APPARATUS,DRIVING CIRCUIT, AND DRIVING METHOD”, filed on Feb. 14, 2014, whichclaims the priority to Chinese Patent Application No. 201310753359.1,titled “TOUCH DISPLAY APPARATUS, DRIVING CIRCUIT, AND DRIVING METHOD”,filed with the Chinese State Intellectual Property Office on Dec. 31,2013, both of which are incorporated herein by reference in entirety.

FIELD

The disclosure relates to the field of touch technology, and inparticular to a touch display apparatus, a driving circuit and a drivingmethod.

BACKGROUND

Currently, a touch panel, as input medium, is a most simple, convenientand natural means for human-computer interaction.

Reference is made to FIG. 1, a liquid crystal display apparatus with anin-cell touch panel (In-cell touch panel) according to the conventionaltechnology is shown. The liquid crystal display apparatus includes, frombottom to top, a thin film transistor (TFT, Thin Film Transistor)substrate 1, a liquid crystal layer (Liquid Crystal) 2 and a colorfilter (CF, Color Filter) substrate 3. The TFT substrate includes afirst glass substrate 11, and thin film transistors 12 arranged on thefirst glass substrate 11. The CF substrate includes, from bottom to top,a common electrode 31, a color filter 32, a touch screen 33 and a secondglass substrate 34. The touch screen 33 in FIG. 1 may be aself-capacitive touch screen. The self-capacitive touch screen detectscapacitance formed by a driving electrode or a sensing electrode and theground, and position detection is performed based on change in thecapacitance caused by a finger touching the touch panel.

During the display of the liquid crystal display apparatus, a liquidcrystal display driving circuit switches on the thin film transistors 12row by row via a gate line, a data line provides a pixel voltage to apixel electrode 35 of each sub-pixel, and the pixel voltage is providedto the common electrode 31. Reference is made to FIG. 2, an equivalentcircuit diagram of a sub-pixel unit in the liquid crystal displayapparatus shown in FIG. 1 is shown. An equivalent capacitor Clc isformed by the pixel electrode 35 and the common electrode 31. Anelectric field in the equivalent capacitor Clc may pass through liquidcrystal molecules in the liquid crystal layer 2. The magnitude of theelectric field determines an angle of rotation of the liquid crystalmolecule, which in turn determines the strength of the light passingthrough this sub-pixel in a specific direction.

With increased requirement on lightness and thinness for the touchpanel, the common electrode is reused as a detection electrode forself-capacitance touch detection. As shown in FIG. 3, a schematicdiagram of a common electrode is shown. The common electrode includesmultiple block electrodes 36 in four rows and four columns. Each of theblock electrodes 36 is connected to a driving chip 37 via a connectingline. The driving chip 37 drives the multiple block electrodes 36 in atime-sharing manner. That is, the driving chip 37 drives the commonelectrode to a potential required for display during a display stage,and provides a touch detection signal to the common electrode during atouch detecting stage.

However, the common electrode forms multiple parasitic capacitors duringthe touch detecting stage, which affects the accuracy of the touchdetection. Reference is made to FIG. 4, an equivalent circuit diagram ofthe sub-pixel unit of the touch display apparatus of the commonelectrode as shown in FIG. 3 is shown. The common electrode is used as atouch detection electrode. Thus, a parasitic capacitor Cmg is formedbetween the common electrode and a gate line, a parasitic capacitor Cmsis formed between the common electrode and a data line, and a parasiticcapacitor Cs is formed between the common electrode and an outline of ascreen body. The parasitic capacitors would interfere with the touchdetection.

SUMMARY

The problem to be solved by the present disclosure is to provide a touchdisplay apparatus, a driving circuit and a driving method for reducingthe interference to the touch detection from a parasitic capacitor andimprove the accuracy of the touch detection.

To solve the above problem, it is provided a touch display apparatus forrealizing touch sensing and displaying according to the presentdisclosure. The touch display apparatus includes: a first substrate; asecond substrate arranged opposite to the first substrate, where gatelines, data lines and thin film transistors are arranged on a surface ofthe second substrate facing towards the first substrate; a liquidcrystal layer arranged between the first substrate and the secondsubstrate; a common electrode arranged between the first substrate andthe second substrate and used as a touch sensing electrode during atouch sensing stage; and a driving circuit configured to provide a firstsignal to the common electrode for realizing touch detection during thetouch sensing stage, where the driving circuit is further configured toprovide a second signal to the gate line during the touch sensing stage,where the second signal is used to control the thin film transistor tobe switched off and is used to decrease charge and discharge capacity ofa capacitor formed by the common electrode and the gate line; and/or thedriving circuit is further configured to provide a third signal to thedata line during the touch sensing stage, where the third signal is usedto decrease charge and discharge capacity of a capacitor formed by thecommon electrode and the data line.

Optionally, the second signal may be a pulse signal with a samefrequency and a same phase as the first signal.

Optionally, the second signal may be a pulse signal with a samefrequency, a same phase and a same amplitude as the first signal.

Optionally, the third signal may be a pulse signal with a same frequencyand a same phase as the first signal.

Optionally, the third signal may be a pulse signal with a samefrequency, a same phase and a same amplitude as the first signal.Optionally, the third signal may be a signal used to control the dataline to enter a floating state.

Optionally, the first signal, the second signal or the third signal maybe a square signal, a sine wave signal or a stair-step signal.

Optionally, the driving circuit may be further configured to: provide adriving signal to the gate line, provide a display signal to the dataline, and provide a common voltage signal to the common electrode,during a display stage.

Optionally, the driving circuit may include: a common electrode drivingunit configured to generate the common voltage signal and a first pulsesignal; a gate driving unit connected to multiple gate lines, where thegate driving unit may be configured to generate the driving signal, andis further configured to generate a second pulse signal with a samefrequency as the first pulse signal; a data line driving unit connectedto multiple data lines, and configured to generate the display signal;and a timing control unit connected to the common electrode drivingunit, the gate driving unit and the data line driving unit, where thetiming control unit may be configured to, during the display stage,control the gate driving unit to provide the driving signal to themultiple gate lines sequentially, control the data line driving unit toprovide the display signal to the data line, and control the commonelectrode driving unit to provide the common voltage signal to thecommon electrode; and the timing control unit may be further configuredto, during the touch sensing stage, control the common electrode drivingunit to provide the first pulse signal to the common electrode forrealizing touch detection, and control the gate driving unit to providethe second pulse signal with the same phase as the first pulse signal tothe multiple gate lines.

Optionally, the data line driving unit may be further configured togenerate a third pulse signal with a same frequency as the first pulsesignal; and the timing control unit may be further configured to controlthe data line driving unit to provide the third pulse signal with thesame phase as the first pulse signal to the multiple data lines duringthe touch sensing stage.

Optionally, the driving circuit may further include switches arrangedbetween the data line driving unit and the multiple data lines, and thedata line driving unit may be configured to provide a pixel voltage tothe data line as a display signal in a case that the switch is on; andthe timing control unit may be connected to the switch, the timingcontrol unit may be configured to control the switch to be switched onduring the display stage to control the data line driving unit toprovide the pixel voltage to the data line, and the timing control unitmay be further configured to control the switch to be switched offduring the touch sensing stage to control the data line to enter afloating state.

Optionally, the driving circuit may include: a common electrode drivingunit configured to generate the common voltage signal and the firstpulse signal; a gate driving unit connected to multiple gate lines, andconfigured to generate the driving signal; a data line driving unitconnected to multiple data lines, where the data line driving unit maybe configured to generate a display signal, and may be furtherconfigured to generate a third pulse signal with a same frequency as thefirst pulse signal; or a data line driving unit being coupled to themultiple data lines via a switch; and a timing control unit connected tothe common electrode driving unit, the gate driving unit and the dataline driving unit, where the timing control unit may be configured to,during the display stage, control the gate driving unit to provide thedriving signal to the multiple gate lines sequentially, control the dataline driving unit to provide the display signal to the data line, andcontrol the common electrode driving unit to provide the common voltagesignal to the common electrode; and the timing control unit may befurther configured to, during the touch sensing stage, control thecommon electrode driving unit to provide the first pulse signal to thecommon electrode for realizing touch detection, and control the dataline driving unit to provide the third pulse signal with the same phaseas the first pulse signal to the multiple data lines or control theswitch to be switched off to control the data line to enter a floatingstate.

Optionally, the driving circuit may be directly connected to the gateline.

Optionally, the driving circuit may be connected to the gate line in acapacitive coupling manner.

Accordingly, it is further provided a driving circuit for driving atouch display apparatus according to the present disclosure. The touchdisplay apparatus includes: a first substrate; a second substratearranged opposite to the first substrate, where gate lines, data linesand thin film transistors are arranged on a surface of the secondsubstrate facing towards the first substrate; a liquid crystal layerarranged between the first substrate and the second substrate; and acommon electrode arranged between the first substrate and the secondsubstrate and used as a touch sensing electrode during a touch sensingstage. The driving circuit includes: a first driving module configuredto provide a first signal to the common electrode for realizing touchdetection during the touch sensing stage; a second driving moduleconfigured to provide a second signal to the gate line during the touchsensing stage, where the second signal is used to control the thin filmtransistor to be switched off and is used to decrease charge anddischarge capacity of a capacitor formed by the common electrode and thegate line; and/or a third driving module configured to provide a thirdsignal to the data line during the touch sensing stage, where the thirdsignal is used to decrease charge and discharge capacity of a capacitorformed by the common electrode and the data line.

Optionally, the second signal may be a pulse signal with a samefrequency and a same phase as the first signal.

Optionally, the second signal may be a pulse signal with a samefrequency, a same phase and a same amplitude as the first signal.

Optionally, the third signal may be a pulse signal with a same frequencyand a same phase as the first signal.

Optionally, the third signal may be a pulse signal with a samefrequency, a same phase and a same amplitude as the first signal.

Optionally, the third signal may be a signal used to control the dataline to enter a floating state.

Optionally, the first signal, the second signal or the third signal maybe a square signal, a sine wave signal or a stair-step signal.

Optionally, the first driving module may be further configured toprovide a common voltage signal to the common electrode during a displaystage, the second driving module may be further configured to provide adriving signal to the gate line during the display stage, and the thirddriving module may be further configured to provide a display signal tothe data line during the display stage.

Optionally, the driving circuit may include: a common electrode drivingunit configured to generate the common voltage signal and a first pulsesignal; a gate driving unit connected to multiple gate lines, where thegate driving unit may be configured to generate the driving signal, andmay be further configured to generate a second pulse signal with a samefrequency as the first pulse signal; a data line driving unit connectedto multiple data lines, and configured to generate the display signal; atiming control unit connected to the common electrode driving unit, thegate driving unit and the data line driving unit, where the timingcontrol unit may be configured to, during the display stage, control thegate driving unit to provide the driving signal to the multiple gatelines sequentially, control the data line driving unit to provide thedisplay signal to the data line, control the common electrode drivingunit to provide the common voltage signal to the common electrode, andthe timing control unit may be further configured to, during the touchsensing stage, control the common electrode driving unit to provide thefirst pulse signal to the common electrode for realizing touchdetection, and control the gate driving unit to provide the second pulsesignal with the same phase as the first pulse signal to the multiplegate lines.

Optionally, the data line driving unit may be further configured togenerate a third pulse signal with a same frequency as the first pulsesignal; and the timing control unit may be further configured to controlthe data line driving unit to provide the third pulse signal with thesame phase as the first pulse signal to the multiple data lines duringthe touch sensing stage.

Optionally, the driving circuit may further include switches arrangedbetween the data line driving unit and the multiple data lines, and thedata line driving unit may be configured to provide a pixel voltage tothe data line as a display signal in a case that the switch is on; andthe timing control unit may be connected to the switch, the timingcontrol unit may be configured to control the switch to be switched onduring the display stage to control the data line driving unit toprovide the pixel voltage to the data line; and the timing control unitmay be further configured to control the switch to be switched offduring the touch sensing stage to control the data line to enter afloating state.

Optionally, the driving circuit may include: a common electrode drivingunit configured to generate the common voltage signal and the firstpulse signal; a gate driving unit connected to multiple gate lines, andconfigured to generate the driving signal; a data line driving unitconnected to multiple data lines, where the data line driving unit maybe configured to generate a display signal, and may be furtherconfigured to generate a third pulse signal with a same frequency as thefirst pulse signal; or a data line driving unit connected to themultiple data lines via a switch; and a timing control unit connected tothe common electrode driving unit, the gate driving unit and the dataline driving unit, where the timing control unit may be configured to,during the display stage, control the gate driving unit to provide thedriving signal to the multiple gate lines sequentially, control the dataline driving unit to provide the display signal to the data line, andcontrol the common electrode driving unit to provide the common voltagesignal to the common electrode, and the timing control unit may befurther configured to, during the touch sensing stage, control thecommon electrode driving unit to provide the first pulse signal to thecommon electrode for realizing touch detection, and control the dataline driving unit to provide the third pulse signal with the same phaseas the first pulse signal to the multiple data lines or control theswitch to be switched off to control the data line to enter a floatingstate.

Optionally, the first driving module may be directly connected to thegate line.

Optionally, the first driving module may be connected to the gate linein a capacitive coupling manner.

Accordingly, it is provided a driving method for driving a touch displayapparatus according to the present disclosure. The touch displayapparatus includes: a first substrate; a second substrate arrangedopposite to the first substrate, where gate lines, data lines and thinfilm transistors are arranged on a surface of the second substratefacing towards the first substrate; a liquid crystal layer arrangedbetween the first substrate and the second substrate; and a commonelectrode arranged between the first substrate and the second substrateand used as a touch sensing electrode during a touch sensing stage. Thedriving method includes: providing a driving signal to the multiple gatelines sequentially, providing a display signal to the data line, andproviding a common voltage signal to multiple electrode units of thecommon electrode, during a display stage; and providing a first signalto the common electrode for realizing touch detection during the touchsensing stage; providing a second signal to the gate line in the processof providing the first signal to the common electrode, where the secondsignal is used to control the thin film transistor to be switched offand is used to decrease charge and discharge capacity of a capacitorformed by the common electrode and the gate line; and/or providing athird signal in the process of providing the first signal to the commonelectrode, where the third signal is used to decrease charge anddischarge capacity of a capacitor formed by the common electrode and thedata line. The second signal may be a pulse signal with a same frequencyand a same phase as the first signal.

Optionally, the second signal is a pulse signal with a same frequency, asame phase and a same amplitude as the first signal.

Optionally, the third signal may be a pulse signal with a same frequencyand a same phase as the first signal.

Optionally, the third signal may be a pulse signal with a samefrequency, a same phase and a same amplitude as the first signal.

Optionally, the third signal may be a signal used to control the dataline to enter a floating state.

Optionally, the first signal, the second signal or the third signal maybe a square signal, a sine wave signal or a stair-step signal.

Compared with the conventional technology, the technical solutionaccording to the present disclosure has the following advantages:

with the driving circuit of the touch display apparatus according to thepresent disclosure, during the touch sensing stage, the first signal isprovided to the common electrode, the second signal is provided to thegate line and/or the third signal is provided, thus charge and dischargecapacity of a parasitic capacitor formed by the common electrode and/orthe gate line is decreased. Interference of the parasitic capacitor tothe touch detection is reduced by decreasing the charge and dischargecapacity of the parasitic capacitor, thus the accuracy of touchdetection is improved.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of a liquid crystal display apparatus withan in-cell touch panel according to the conventional technology;

FIG. 2 is an equivalent circuit diagram of a sub-pixel unit as shown inFIG. 1;

FIG. 3 is a schematic diagram of a common electrode having a function ofself-capacitive touch detection according to the conventionaltechnology;

FIG. 4 is an equivalent circuit diagram of a sub-pixel unit of a touchdisplay apparatus in which a conventional common electrode is reused asa touch electrode according to the conventional technology;

FIG. 5 is a schematic diagram of a touch display apparatus according toan embodiment of the present disclosure;

FIG. 6 is a schematic diagram of a driving signal of the touch displayapparatus shown in FIG. 5;

FIG. 7 is a schematic diagram of a driving circuit shown in FIG. 5according to an embodiment;

FIG. 8 is a schematic diagram of a gate driving unit shown in FIG. 5according to an embodiment;

FIG. 9 is a schematic diagram of a common electrode driving unit shownin FIG. 5 according to an embodiment;

FIG. 10 is a schematic diagram of a data line driving unit shown in FIG.5 according to an embodiment; and

FIG. 11 is a schematic diagram of a touch display apparatus according toanother embodiment of the present disclosure.

DETAILED DESCRIPTION OF EMBODIMENTS

To make the above features and advantages of the disclosure moreapparent and easier to be understood, specific embodiments of thedisclosure are illustrated in detail hereinafter in conjunction with thedrawings.

To solve the problem mentioned in the background, it is provided a touchdisplay apparatus according to the present disclosure. Reference is madeto FIG. 5, a schematic diagram of a touch display apparatus according toan embodiment of the present disclosure is shown. The touch displayapparatus includes a first substrate (not shown), a second substrate111, a liquid crystal layer, a common electrode 105 and a drivingcircuit 100.

The first substrate is used as a glass substrate at a side of a colorfilter (Color Filter, CF).

The second substrate 111 is used as a glass substrate at a side of athin film transistor (Thin Film Transistor, TFT). The second substrate111 is arranged opposite to the first substrate.

Multiple gate lines G₁, G₂ . . . G_(M), multiple data lines S₁, S₂ . . .S_(N) and thin film transistors 104 are arranged on a surface of thesecond substrate 111 facing towards the first substrate. A drain of thethin film transistor 106 is connected to a pixel electrode (not shown).The multiple gate lines G₁, G₂ . . . G_(M) are electrically connected togates of the thin film transistors 104, and configured to providedriving signals to the gates of the thin film transistors 104. Themultiple data lines S₁, S₂ . . . S_(N) are connected to sources of thethin film transistors 104, and are configured to provide pixel voltagesto the sources of the thin film transistors 106.

The liquid crystal layer (not shown) is arranged between the firstsubstrate and the second substrate 111.

The common electrode 105 is arranged between the first substrate and thesecond substrate 111. The common electrode 105 is used as a touchsensing electrode during a touch sensing stage, and is provided with acommon voltage (VCOM) during a display stage. Specifically, the commonelectrode 105 may include multiple electrode units arranged in a matrix,and the multiple electrode units are detection electrodes for realizingself-capacitive detection in the touch sensing.

The driving circuit 100 is configured to provide a first signal to thecommon electrode 105 for realizing touch detection during the touchsensing stage. The driving circuit 100 is further configured to providea second signal to the gate lines G₁, G₂ . . . G_(M) during the touchsensing stage. The second signal is used to control the thin filmtransistor to be switched off and is used to decrease charge anddischarge capacity of a capacitor formed by the common electrode and thegate line. And/or, the driving circuit 100 is further configured toprovide a third signal during the touch sensing stage. The third signalis used to decrease charge and discharge capacity of a capacitor formedby the common electrode and the data line.

It should be noted that, to decrease the charge and discharge capacityof the capacitor formed by the common electrode 105 and the gate line(the data line) herein refers to: to decrease the charge and dischargecapacity as compared with that of a capacitor in a case that no secondsignal (no third signal).

With the touch display apparatus according to the embodiment, the firstsignal provided to the common electrode and the second signal (the thirdsignal) by the driving circuit can decrease the charge and dischargecapacity of the parasitic capacitor formed by the common electrode andthe gate line (the data line), thus interference of the parasiticcapacitor to the touch detection is reduced, and accuracy of the touchdetection is improved.

Next, a principle of improving the accuracy of the touch detection bythe touch display apparatus according to the embodiment shown in FIG. 5is explained in conjunction with a driving signal shown in FIG. 6.

As shown in FIG. 5, the driving circuit 100 in the embodiment includes acommon electrode driving unit 103, a gate driving unit 101, a data linedriving unit 102 and a timing control unit (not shown).

The common electrode driving unit 103 is connected to the commonelectrode 105, and is configured to generate the common voltage signalVCOM and a first pulse signal 201 which is the first signal. The firstpulse signal 201 here is a square signal with a low level of 0V and ahigh level of 2V. The first pulse signal 201 is a detection signalprovided to the common electrode used as the touch sensing electrode forrealizing touch detection.

The gate driving unit 101 is connected to multiple gate lines G₁, G₂ . .. G_(M) and is configured to generate a second pulse signal 202. Thegate driving unit 101 may be directly connected to the gate lines G₁, G₂. . . G_(M), or may be connected to the gate lines G₁, G₂ . . . G_(M) ina capacitive coupling manner.

The second pulse signal 202 is the second signal, and the second pulsesignal 202 here is a square signal with a low level of −12V and a highlevel of −10V. The second pulse signal 202 is a pulse signal with a samefrequency and a same amplitude (which is 2V) as the first pulse signal201. The high level of the second pulse signal 202 is much smaller thana threshold voltage of the thin film transistor 104, so that the thinfilm transistor 104 is switched off, thereby not affecting a signalprovided to a liquid crystal box during the touch sensing stage, andrealizing a normal display function of the touch display apparatus.

The data line driving unit 102 is connected to multiple data lines S₁,S₂ . . . S_(N) and is configured to generate a third pulse signal 203which is the third signal. The third pulse signal 203 here is a squaresignal with a low level of 0V and a high level of 2V. The third pulsesignal 203 is a pulse signal with a same frequency and a same amplitude(which is 2V) as the first pulse signal 201.

The timing control unit is connected to the common electrode drivingunit 103, the gate driving unit 101 and the data line driving unit 102,and configured to, during the touch sensing stage, control the commonelectrode driving unit 201 to provide the first pulse signal to thecommon electrode 105 for realizing touch detection, control the gatedriving unit 101 to provide the second pulse signal 202 with the samephase as the first pulse signal 201 to the multiple gate lines G₁, G₂ .. . G_(M), and control the data line driving unit 102 to provide thethird pulse signal 230 with a same phase as the first pulse signal 201to the multiple data lines S₁, S₂ . . . S_(N).

In the driving circuit 100 of the touch display apparatus according tothe embodiment, the second pulse signal 202 with a same frequency, asame phase and a same amplitude as the first pulse signal 201 isprovided to multiple gate lines G₁, G₂ . . . G_(M) by the gate drivingunit 101 during the touch sensing stage. Thus, even a capacitor isformed by the common electrode 105 and the gate lines G₁, G₂ . . .G_(M), the capacitor is not charged and discharged, since signals withsame frequency, a same phase and a same amplitude are provided to twoelectrode plates formed by the common electrode 105 and the gate linesG₁, G₂ . . . G_(M), that is, voltages of same magnitude are provided tothe two electrode plates of the capacitor at any time. Hence, charge anddischarge capacity of the capacitor formed by the common electrode 105and the gate lines G₁, G₂ . . . G_(M) is zero. Compared with a case thatthe second pulse signal 202 is not provided to the gate lines G₁, G₂ . .. G_(M), the charge and discharge capacity is decreased up to zero. Thatis, the capacitor formed by the common electrode 105 and the gate linesG₁, G₂ . . . G_(M) does not interfere with touch detection in apractical circuit, and thus the accuracy of the touch detection isimproved.

In the driving circuit 100 of the touch display apparatus according tothe embodiment, the third pulse signal 203 with a same frequency, a samephase and a same amplitude as the first pulse signal 201 is provided tomultiple data lines S₁, S₂ . . . S_(N) by the data line driving unit 102during the touch sensing stage. Thus, even a capacitor is formed by thecommon electrode 105 and the data lines S₁, S₂ . . . S_(N), thecapacitor is not charged and discharged, since signals with samefrequency, a same phase and a same amplitude are provided to twoelectrode plates formed by the common electrode 105 and the data linesS₁, S₂ . . . S_(N), that is, voltages of same magnitude are provided tothe two electrode plates of the capacitor at any time. Hence, charge anddischarge capacity of the capacitor formed by the common electrode 105and the data lines S₁, S₂ . . . S_(N) is zero. Compared with a case thatthe third pulse signal 203 is not provided to the data lines S₁, S₂ . .. S_(N), the charge and discharge capacity is decreased up to zero. Thatis, the capacitor formed by the common electrode 105 and the data linesS₁, S₂ . . . S_(N) does not interfere with touch detection in apractical circuit, and thus the accuracy of the touch detection isimproved.

It should also be noted that, the second pulse signal 202 and the thirdpulse signal 203 each have a same frequency, a same phase and a sameamplitude as the first pulse signal 201, so that the capacitor formed bythe common electrode and the gate lines (the data lines) is not chargedand discharged, which are not limited thereto in the present disclosure,as long as the second pulse signal 202 and the third pulse signal 203each have a same frequency and a same phase as the first pulse signal201. Even magnitudes of voltage provided to two electrode plates of thecapacitor are different at any time, a potential difference between theelectrode plates of the capacitor is decreased compared with a case thatno signal is provided to the gate lines, since signals of two electrodeplates have same frequency and a same phase. Thus, the charge anddischarge capacity of the capacitor formed by the common electrode 105and the gate lines G₁, G₂ . . . G_(M) (the data lines S₁, S₂ . . .S_(N)) is reduced.

It should be further noted that, the first signal, the second signal andthe third signal in an embodiment each are pulse signals, which is notlimited in the present disclosure, as long as the signal is a signalprovided to the common electrode 105, the gate lines G₁, G₂ . . . G_(M)and the data lines S₁, S₂ . . . S_(N) so to decrease the charge anddischarge capacity of the capacitor.

It should be further noted that, the first signal, the second signal andthe third signal in an embodiment each are square signals, which is notlimited in the present disclosure. The first signal, the second signaland the third signal in another embodiment may be sine wave signals orstair-step signals.

The driving circuit 100 of the touch display apparatus in the embodimentcan reduce an effect of the parasitic capacitor between the commonelectrode 105 and the gate lines G₁, G₂ . . . G_(M), and can reduce aneffect of the parasitic capacitor between the common electrode 105 andthe data lines S₁, S₂ . . . S_(N), which is not limited in the presentdisclosure. In a touch display apparatus according to anotherembodiment, only the gate driving unit 101 may be arranged, for reducinginterference of the parasitic capacitor between the common electrode 105and the gate lines G₁, G₂ . . . G_(M) to the touch detection. In theembodiment in which only the gate driving unit 101 is arranged, thetiming control unit only controls the gate driving unit 101 to providethe second pulse signal 202 with a same phase as the first pulse signal201 to the multiple gate lines G₁, G₂ . . . G_(M).

Alternatively, in a touch display apparatus according to anotherembodiment, only the data line driving unit 102 may be arranged, forreducing interference of the parasitic capacitor between the commonelectrode 105 and the data lines S₁, S₂ . . . S_(N) to the touchdetection. In the embodiment in which only the data line driving unit102 is arranged, the timing control unit only controls the data linedriving unit 102 to provide the third pulse signal 203 with a same phaseas the first pulse signal 201 to the multiple data lines S₁, S₂ . . .S_(N).

Reference is made to FIG. 5 and FIG. 6 continuously, the driving circuit100 of the touch display apparatus according to the embodiment serves toperform both driving display and driving touch detection. A circuit partof driving display and a circuit part of driving touch detectiontogether are integrated into the driving circuit 100.

Specifically, the driving circuit 100 is further configured to provide adriving signal to the gate lines G₁, G₂ . . . G_(M), provide a displaysignal to the data lines S₁, S₂ . . . S_(N), and provide a commonvoltage signal to the common electrode 105, during a display stage,which is not limited in the present disclosure. In another embodiment,the driving circuit may only function to perform the driving touchdetection, as long as the driving circuit can reduce the interference ofthe parasitic capacitor during the touch sensing stage.

Specifically, the driving circuit 100 includes a total timing controller(not shown) and is configured to drive to the display stage and thetouch sensing stage in a time-sharing manner. The driving circuit 100during the touch sensing stage is not described herein, and referencemay be made to the above description. In the following, an operation ofthe driving circuit 100 during the display stage is introduced indetail.

As shown in FIG. 6, the gate driving unit 101 of the driving circuit 100is further configured to generate the driving signal. Specifically, thedriving circuit herein generates timing pulse signals driving the gatelines G₁, G₂ . . . G_(M) sequentially, and the pulse signal is a pulsesignal with a high level of 15V and a low level of 0V.

The data line driving unit 102 is further configured to generate adisplay signal D.

The common electrode driving unit 103 is further configured to generatea common voltage signal VCOM.

The timing control unit is connected to the common electrode drivingunit 103, the gate driving unit 101 and the data line driving unit 102.The timing control unit is configured to, during the display stage,control the gate driving unit 101 to provide a driving signal tomultiple gate lines G₁, G₂ . . . G_(M) sequentially, control the dataline driving unit 102 to provide the display signal D to the data linesS_(j), S₂ . . . S_(N), and control the common electrode driving unit 103to provide the common voltage signal VCOM to the common electrode 105.The timing control unit is further configured to, during the touchsensing stage, control the common electrode driving unit 103 to providethe first pulse signal 201 to the common electrode 105 for realizingtouch detection, and control the gate driving unit 101 to provide thesecond pulse signal 202 with a same phase as the first pulse signal 201to the multiple gate lines G₁, G₂ . . . G_(M). The timing control unitis further configured to control the data line driving unit 102 toprovide the third pulse signal 202 with a same phase as the first pulsesignal to multiple data lines S_(j), S₂ . . . S_(N) during the touchsensing stage.

In the following, the driving circuit 100 is further explained inconjunction with a specific circuit.

Reference is made to FIG. 7, a schematic diagram of a driving circuitshown in FIG. 5 according to an embodiment is shown. The driving circuit100 in the embodiment further includes an on-screen gate circuit 106arranged on a screen (a region of a dashed box shown in FIG. 5). Itshould be noted that, a touch display apparatus with a resolution of1280×720 RGB is taken as an example herein. 640 gate lines are generatedat each side of the screen on right and left. Specifically, theon-screen gate circuit 106 is formed by connecting 640 RS Cellsub-circuits (the RS Cell is used as a latch). In the RS Cellsub-circuit, VGL end is connected to a voltage source provided to thegate line for turning off a thin film transistor TFT, CK end isconnected to a clock input signal, SP end is a data input end, and OUTis an output end.

Logic control signals provided to the RS Cell sub-circuit by the gatedriving unit 101 include: CK1_L, CK2_L, SP_L, CK1_R, CK2_R, SP_R andVGLO for driving the gate lines G₁, G₂ . . . G_(M) (M is 1280).

Reference is made to FIG. 8, a schematic diagram of a gate driving unit101 shown in FIG. 5 according to an embodiment is shown. The gatedriving unit 101 includes a charge pump 1012, a voltage regulator 1013,multiple high voltage driving units 1015, a power signal unit 1014 and atiming control unit 1011.

The charge pump 1012 includes a first output terminal configured tooutput a first voltage VGH (15V) for driving the thin film transistor toturn on; and a second output terminal configured to output a secondvoltage VGL1 (−12V) for controlling the thin film transistor to turnoff.

The voltage regulator 1013 is connected to the second output terminal ofthe charge pump 1012 and is configured to adjust the second voltageoutputted by the charge pump 1012 to form a third voltage VGL2 (−10V).The second voltage and the third voltage correspond to a low level and ahigh level of the second pulse signal 202 respectively.

An input terminal of the multiple high voltage driving units 1015 isconnected to the first output terminal and the second output terminal ofthe charge pump 1012 and the voltage regulator 1013. An output terminalof the high voltage driving units 1015 is connected to the SP end, whichis the data input terminal, of the RS Cell sub-circuit and the CK endfor outputting the logic control signals CK1_L, CK2_L, SP_L, CK1_R,CK2_R and SP_R.

Specifically, the high voltage driving unit 1015 includes a first PMOStransistor P1, a first NMOS transistor N1A and a second NMOS transistorN1B. A source of the first PMOS transistor Pb is connected to the firstoutput terminal of the charge pump 1012 (provided with the first voltageVGH), and a gate of the first MOS transistor P1 is connected to a firsttiming controller (not shown). A source of the first NMOS transistor N1Ais connected to the second output terminal of the charge pump 1012(provided with the second voltage VGL), and a gate of the first NMOStransistor N1A is connected to a third timing controller and a secondtiming controller. A source of the second NMOS transistor N1B isconnected to the voltage regulator 1013 (provided with the third voltageVGL2), a gate of the second NMOS transistor N1B is connected to thesecond timing controller, and a drain of the second NMOS transistor N1Bis connected to a drain of the first NMOS transistor N1A and a drain ofthe first PMOS transistor P1.

An input terminal of the power signal unit 1014 is connected to thesecond output terminal of the charge pump 1012 and the voltageregulator, and an output terminal of the power signal unit 1014 isconnected to a voltage source VGL input terminal of the multiple RS Cellsub-circuits.

Specifically, the power signal unit 1014 includes a third NMOStransistor N2A and a fourth NMOS transistor N2B. A source of the thirdNMOS transistor N2A is connected to a third output terminal of thecharge pump 1012, and a gate of the third NMOS transistor N2A isconnected to the second timing controller. A source of the fourth NMOStransistor N2B is connected to an output terminal of the voltageregulator 1013, a gate of the fourth NMOS transistor N2B is connected tothe second timing controller, and a drain of the fourth NMOS transistorN2B is connected to a drain of the third NMOS transistor.

The timing control unit 1011 includes a first timing controller (notshown). The first timing controller is connected to the high voltagedriving unit 1015 for driving the high voltage driving unit 1015 tooutput the first voltage VGH and the second voltage VGL1 alternately toprovide the first voltage VGH and the second voltage VGL1 to themultiple gate lines in a time-sharing manner, thereby providing adriving signal to multiple gate lines in a time-sharing manner to beused in the display stage.

The timing control unit 1011 further includes a second timingcontroller. The second timing controller is connected to the highvoltage driving unit 1015 and the power signal unit 1014. The secondtiming controller is configured to drive the power signal unit 1014 tooutput the second voltage VGL1 and the third voltage VGL2 to an inputterminal of the voltage source VGL of the RS Cell sub-circuitalternately. The second timing controller is further configured tocontrol the high voltage driving unit 1015 to output the second voltageVGL1 and the third voltage VGL2 to the data input terminal SP of the RSCell sub-circuit alternately, so that a signal from the voltage sourceVGL input terminal of the RS Cell sub-circuit is outputted to the outputterminal OUT of the RS Cell sub-circuit to provide the second pulsesignal 202 to multiple gate lines to be used in the touch sensing stage.

The timing control unit 1011 further includes a total timing controller(not shown). The total timing controller is connected to the firsttiming controller and the second timing controller, and is configured tocontrol the first timing controller to perform the driving during thedisplay stage and control the second timing controller to perform thedriving during the touch sensing stage.

Reference is made to FIG. 9, a schematic diagram of a data line drivingunit shown in FIG. 5 according to an embodiment is shown. Specifically,the data line driving unit includes a timing control unit 1011 andmultiple data line signal buffers 1023.

The multiple data line signal buffers 1023 correspond to multiple datalines S₁, S₂ . . . S_(N) respectively.

The data line signal buffer 1023 includes a positive driving circuit1021 and a negative driving circuit 1022.

An output terminal of the positive driving circuit 1021 is connected tothe corresponding one of the data lines for generating a first pixelvoltage driving liquid crystal molecules to rotate towards a firstdirection as the display signal, and a first switch T1A is arranged nearthe output terminal of the positive driving circuit.

An output terminal of the negative driving circuit 1022 is connected tothe corresponding one of the data lines for generating a second pixelvoltage driving liquid crystal molecules to rotate towards a seconddirection as a display signal, and a second switch T1D is arranged nearthe output terminal of the negative driving circuit.

The data line driving unit further includes a third switch T1B and afourth switch T1C. One end of the third switch T1B is connected to avoltage source VSP (a voltage of which is 2V), and the other end of thethird switch T1B is connected to an output terminal of the data linedriving unit. One end of the fourth switch T1C is connected to theground, and the other end of the fourth switch T1C is connected to theoutput terminal of the data line driving unit.

The timing control unit 1011 further includes a third timing controller(not shown). The third timing controller is driven by the total timingcontroller during the display stage, and is connected to the positivedriving circuit 1021 and the negative driving circuit 1022. The thirdtiming controller is configured to drive the first switch T1A and thesecond switch T1D to be switched on alternately, so that the positivedriving circuit and the negative driving circuit output the first pixelvoltage and the second pixel voltage respectively.

The timing control unit 1011 further includes a fourth timingcontroller. The fourth timing controller is driven by the total timingcontroller during the touch sensing stage, and is configured to drivethe third switch T1B (not shown) and the fourth switch T1C to beswitched on alternately, so as to output the third pulse signal 203 witha high level being a voltage of the voltage source and a low level of 0Vin a time-sharing manner.

Reference is made to FIG. 10, which is a schematic diagram of a commonelectrode driving unit shown in FIG. 1 according to an embodiment. Thecommon electrode driving unit includes a touch detection circuit 1033, acommon electrode driving buffer 1032 and a timing control unit 1011.

The touch detection circuit 1033 is connected to multiple electrodeunits of the common electrode 105 via first switches K1A, K2A . . . KNArespectively, and is configured to provide the first pulse signal to themultiple electrode units in a case that the first switches K1A, K2A . .. KNA are switched on for realizing touch detection.

The common electrode driving buffer 1032 is connected to the multipleelectrode units of the common electrode 105 via second switches K1B, K2B. . . KNB respectively, and is configured to provide the common voltagesignal to the multiple electrode units in a case that the secondswitches K1B, K2B . . . KNB are switched on.

The timing control unit 1011 is connected to the first switches K1A, K2A. . . KNA and the second switches K1B, K2B . . . KNB. The timing controlunit 1011 is configured to drive the first switches K1A, K2A . . . KNAto be switched on during the touch sensing stage so that the touchdetection circuit 1033 performs self-capacitance detection on themultiple electrode units of the common electrode 105. The timing controlunit 1011 is further configured to drive the second switches K1B, K2B .. . KNB to be switched on during the display stage so as to control thecommon electrode driving buffer 1032 to provide the common voltagesignal to the multiple electrode units of the common electrode 105.

It should be noted that, FIG. 8, FIG. 9 and FIG. 10 show specificimplementations of the gate driving unit 101, the data line driving unit102 and the common electrode driving unit 103 respectively, which is notlimited in the present disclosure. In another embodiment, the gatedriving unit 101, the data line driving unit 102 and the commonelectrode driving unit 103 may be implemented in other circuitconfiguration.

Alternatively, in other embodiment, the gate driving unit (or the dataline driving unit) of the driving circuit may realize only the displayfunction. During the touch sensing stage, the data line driving circuitprovides a pulse signal corresponding to the first signal to the dataline (or the gate line driving circuit provides a pulse signalcorresponding to the first signal to the gate line). That is, by onlyreducing the interference of parasitic capacitor formed by the data line(or the gate line) and the common electrode to the touch detection, theaccuracy of the touch detection is improved.

It should be noted that, in the above embodiment, the third signal is asignal provided to the data line by the driving circuit, charge anddischarge capacity of a capacitor is decreased by using the third signalprovided to the data line and the first signal provided to the commonelectrode, which is not limited in the present disclosure. In otherembodiment, the third signal may not be a signal provided to the dataline.

Reference is made to FIG. 11, a schematic diagram of a touch displayapparatus according to another embodiment of the present disclosure isshown. The similarities between this embodiment and the embodiment shownin FIG. 5 are not described. This embodiment is different from theembodiment shown in FIG. 5 in that, the driving circuit is coupled tothe data line via the switch (no shown). The third signal 303 in thisembodiment is a signal for controlling the switch to be switched off andmay control the data line to enter a floating state during the touchsensing stage. In the floating state, the data line connected to thedriving circuit during the display stage is disconnected from thedriving circuit during the touch sensing stage.

Thus, the data line is disconnected from the driving circuit during thetouch sensing stage and is not provided with any signal. Hence, duringthe touch sensing stage, in a capacitor formed by the common electrodeand the data line, an electrode plate corresponding to the data line isnot connected to any device, and the capacitor is not charged anddischarged, thus the charge and discharge capacity is decreased and theaccuracy of the touch detection is improved.

Specifically, the similarities between the driving circuit having boththe display function and the touch detecting function and the previousembodiment are not described. The driving circuit differs from that inthe previous embodiment in that, the driving circuit further includes:switches arranged between the data line driving unit and the multipledata lines, and the data line driving unit is configured to provide apixel voltage to the data line as a display signal in a case that theswitch is on; and the timing control unit is connected to the switch,the timing control unit is configured to control the switch to beswitched on during the display stage to control the data line drivingunit to provide the pixel voltage to the data line, and the timingcontrol unit is further configured to control the switch to be switchedoff during the touch sensing stage via the third signal 303 to controlthe data line to enter a floating state, to decrease the interference ofthe parasitic capacitor formed by the data line and the common electrodeto the touch detection during the touch sensing stage.

It should be noted that, in the embodiment shown in FIG. 11, the gatedriving unit further provides the second pulse signal 302 with a samefrequency, a same phase and a same amplitude as the first pulse signal301 to the multiple gate lines G₁, G₂ . . . G_(M) to reduce theinterference of the parasitic capacitor formed by the common electrodeand the gate line and the interference of the parasitic capacitor formedby the common electrode and the data line. In other embodiment, the gatedriving unit of the driving circuit may realize only the displayfunction, the driving circuit during the touch sensing stage controlsthe data line to enter a floating state. That is, by only reducing theinterference of the parasitic capacitor between the data line and thecommon electrode to the touch detection, the accuracy of the touchdetection is improved.

Accordingly, it is further provided a driving circuit according to thepresent disclosure, which is applied to a touch display apparatus. Thetouch display apparatus includes: a first substrate; a second substratearranged opposite to the first substrate, where gate lines, data linesand thin film transistors are arranged on a surface of the secondsubstrate facing towards the first substrate; a liquid crystal layerarranged between the first substrate and the second substrate; and acommon electrode arranged between the first substrate and the secondsubstrate and used as a touch sensing electrode during a touch sensingstage.

The driving circuit includes: a first driving module configured toprovide a first signal to the common electrode for realizing touchdetection during the touch sensing stage; a second driving moduleconfigured to provide a second signal to the gate line during the touchsensing stage, where the second signal is used to control the thin filmtransistor to be switched off and is used to decrease charge anddischarge capacity of a capacitor formed by the common electrode and thegate line; and/or a third driving module configured to provide a thirdsignal to the data line during the touch sensing stage, where the thirdsignal is used to decrease charge and discharge capacity of a capacitorformed by the common electrode and the data line.

Specifically, the first driving module includes a common electrodedriving unit and a part of the timing control unit for driving thecommon electrode driving unit; the second driving module includes a gatedriving unit and a part of the timing control unit for driving the gatedriving unit; and the third driving module includes a data line drivingunit and a part of the timing control unit for driving the data linedriving unit.

The related description of the driving circuit has been given in therelated embodiment of the touch display apparatus, which is notdescribed herein.

It is further provided a driving method for driving a touch displayapparatus according to the present disclosure. The touch displayapparatus includes: a first substrate; a second substrate arrangedopposite to the first substrate, where gate lines, data lines and thinfilm transistors are arranged on a surface of the second substratefacing towards the first substrate; a liquid crystal layer arrangedbetween the first substrate and the second substrate; and a commonelectrode arranged between the first substrate and the second substrateand used as a touch sensing electrode during a touch sensing stage.

The driving method includes:

providing a driving signal to the multiple gate lines sequentially,providing a display signal to the data line, and providing a commonvoltage signal to multiple electrode units of the common electrode,during a display stage; and

providing a first signal to the common electrode for realizing touchdetection during the touch sensing stage; providing a second signal tothe gate line in the process of providing the first signal to the commonelectrode, where the second signal is used to control the thin filmtransistor to be switched off and is used to decrease charge anddischarge capacity of a capacitor formed by the common electrode and thegate line; and/or providing a third signal in the process of providingthe first signal to the common electrode, where the third signal is usedto decrease charge and discharge capacity of a capacitor formed by thecommon electrode and the data line.

With the driving method according to the present disclosure, during thetouch sensing stage, the first signal is provided to the commonelectrode, the second signal is provided to the gate line and/or thethird signal is provided, thus charge and discharge capacity of aparasitic capacitor formed by the common electrode and the gate lineand/or the data line is decreased. Interference of the parasiticcapacitor to the touch detection is reduced by decreasing the charge anddischarge capacity of the parasitic capacitor, thus the accuracy oftouch detection is improved.

Optionally, the second signal is a pulse signal with a same frequency, asame phase and a same amplitude as the first signal, so that thecapacitor formed by the common electrode and the gate line is notcharged and discharged, that is, the charge and discharge capacity isdecreased to zero, which is not limited in the present disclosure. Inother embodiment, the second is a pulse signal with a same frequency anda same phase as the first signal, and the charge and discharge capacitycan also be decreased.

Optionally, in the process of providing the third signal, the thirdsignal is provided to the data line. The third signal is a pulse signalwith a same frequency, a same phase and a same amplitude as the firstsignal, so that the capacitor formed by the common electrode and thedata line is not charged and discharged, that is, the charge anddischarge capacity is decreased to zero to reduce the interference ofthe parasitic capacitor, which is not limited in the present disclosure.In other embodiment, the third signal is a pulse signal with a samefrequency and a same phase as the first signal, and the charge anddischarge capacity can also be decreased.

Optionally, the third signal may not be a signal provided to the dataline, and may be a signal used to control the data line to enter afloating state. Specifically, the data line may be coupled to thedriving circuit via a switch, and the third signal may be a signal forcontrolling the driving circuit to be disconnected from the data line soas to control the data line to enter a floating state, so that thecapacitor formed by the common electrode and the data line is notcharged and discharged, that is, the charge and discharge capacity isdecreased to zero.

In the driving method according to the present disclosure, a form of thefirst signal, the second signal or the third signal is not limited,which may be a pulse signal, such as a square signal, a sine wave signalor a stair-step signal, or may not be a pulse signal.

It should be noted that, the driving method according to the presentdisclosure may be performed by the driving circuit according to thepresent disclosure, or may be performed by other driving circuit, whichis not limited in the present disclosure.

Although the present invention is disclosed above, the present inventionshould not be limited thereto. Various changes and modifications can bemade by those skilled in the art without departing from the spirit andscope of the present invention. Therefore, the scope of protection ofthe present invention should be defined by the appending claims.

The invention claimed is:
 1. A touch display apparatus for realizingtouch sensing and displaying, comprising: a first substrate; a secondsubstrate arranged opposite to the first substrate, wherein gate lines,data lines and thin film transistors are arranged on a surface of thesecond substrate facing towards the first substrate; a liquid crystallayer arranged between the first substrate and the second substrate; acommon electrode arranged between the first substrate and the secondsubstrate and used as a touch sensing electrode during a touch sensingstage; and a driving circuit configured to provide a first signal to thecommon electrode for realizing touch detection during the touch sensingstage, wherein the driving circuit is further configured to provide asecond signal to the gate line during the touch sensing stage, whereinthe second signal is used to control the thin film transistor to beswitched off and is used to decrease charge and discharge capacity of acapacitor formed by the common electrode and the gate line; wherein thedriving circuit is further configured to provide a third signal duringthe touch sensing stage, wherein the third signal is used to decreasecharge and discharge capacity of a capacitor formed by the commonelectrode and the data line; wherein the second signal is a pulse signalwith a same frequency and a same phase as the first signal, but has adifferent voltage level from the first signal, or the second signal is apulse signal with a same frequency, a same phase, and a same amplitudeas the first signal, but has a different voltage level from the firstsignal; wherein the driving circuit provides the third signal to thedata line, and the third signal is a pulse signal with a same frequency,a same phase, and a same voltage level as the first signal, or the thirdsignal is a pulse signal with a same frequency, a same phase, a samevoltage level, and a same amplitude as the first signal; and wherein thefirst signal, the second signal or the third signal is a square signal,a sine wave signal or a stair-step signal.
 2. The touch displayapparatus according to claim 1, wherein the driving circuit is furtherconfigured to: provide a driving signal to the gate line, provide adisplay signal to the data line, and provide a common voltage signal tothe common electrode, during a display stage.
 3. The touch displayapparatus according to claim 2, wherein the driving circuit comprises: acommon electrode driving unit configured to generate the common voltagesignal and the first signal; a gate driving unit connected to aplurality of gate lines, wherein the gate driving unit is configured togenerate the driving signal, and is further configured to generate thesecond signal; a data line driving unit connected to a plurality of datalines, and configured to generate the display signal; and a timingcontrol unit connected to the common electrode driving unit, the gatedriving unit and the data line driving unit, wherein the timing controlunit is configured to, during the display stage, control the gatedriving unit to provide the driving signal to the plurality of gatelines sequentially, control the data line driving unit to provide thedisplay signal to the data line, and control the common electrodedriving unit to provide the common voltage signal to the commonelectrode; and wherein the timing control unit is further configured to,during the touch sensing stage, control the common electrode drivingunit to provide the first signal to the common electrode for realizingtouch detection, and control the gate driving unit to provide the secondsignal to the plurality of gate lines.
 4. The touch display apparatusaccording to claim 3, wherein the data line driving unit is furtherconfigured to generate the third signal; and the timing control unit isfurther configured to control the data line driving unit to provide thethird signal to the plurality of data lines during the touch sensingstage.
 5. The touch display apparatus according to claim 2, wherein thedriving circuit comprises: a common electrode driving unit configured togenerate the common voltage signal and the first signal; a gate drivingunit connected to a plurality of gate lines, and configured to generatethe driving signal; a data line driving unit connected to a plurality ofdata lines, wherein the data line driving unit is configured to generatea display signal, and is further configured to generate the thirdsignal; and a timing control unit connected to the common electrodedriving unit, the gate driving unit and the data line driving unit,wherein the timing control unit is configured to, during the displaystage, control the gate driving unit to provide the driving signal tothe plurality of gate lines sequentially, control the data line drivingunit to provide the display signal to the data line, and control thecommon electrode driving unit to provide the common voltage signal tothe common electrode; and wherein the timing control unit is furtherconfigured to, during the touch sensing stage, control the commonelectrode driving unit to provide the first signal to the commonelectrode for realizing touch detection, and control the data linedriving unit to provide the third signal to the plurality of data lines.6. The touch display apparatus according to claim 1, wherein the drivingcircuit is directly connected to the gate line; or the driving circuitis connected to the gate line in a capacitive coupling manner.
 7. Adriving circuit for driving a touch display apparatus, wherein the touchdisplay apparatus comprises: a first substrate; a second substratearranged opposite to the first substrate, wherein gate lines, data linesand thin film transistors are arranged on a surface of the secondsubstrate facing towards the first substrate; a liquid crystal layerarranged between the first substrate and the second substrate; and acommon electrode arranged between the first substrate and the secondsubstrate and used as a touch sensing electrode during a touch sensingstage; wherein the driving circuit comprises: a first driving moduleconfigured to provide a first signal to the common electrode forrealizing touch detection during the touch sensing stage; a seconddriving module configured to provide a second signal to the gate lineduring the touch sensing stage, wherein the second signal is used tocontrol the thin film transistor to be switched off and is used todecrease charge and discharge capacity of a capacitor formed by thecommon electrode and the gate line; and a third driving moduleconfigured to provide a third signal during the touch sensing stage,wherein the third signal is used to decrease charge and dischargecapacity of a capacitor formed by the common electrode and the dataline, wherein the second signal is a pulse signal with a same frequencyand a same phase as the first signal, but has a different voltage levelfrom the first signal, or the second signal is a pulse signal with asame frequency, a same phase, and a same amplitude as the first signal,but has a different voltage level from the first signal; wherein thedriving circuit provides the third signal to the data line, and thethird signal is a pulse signal with a same frequency, a same phase, anda same voltage level as the first signal, or the third signal is a pulsesignal with a same frequency, a same phase, a same voltage level, and asame amplitude as the first signal; and wherein the first signal, thesecond signal or the third signal is a square signal, a sine wave signalor a stair-step signal.
 8. The driving circuit according to claim 7,wherein the first driving module is further configured to provide acommon voltage signal to the common electrode during a display stage,the second driving module is further configured to provide a drivingsignal to the gate line during the display stage, and the third drivingmodule is further configured to provide a display signal to the dataline during the display stage.
 9. The driving circuit according to claim8, wherein the driving circuit comprises: a common electrode drivingunit configured to generate the common voltage signal and the firstsignal; a gate driving unit connected to a plurality of gate lines,wherein the gate driving unit is configured to generate the drivingsignal, and is further configured to generate the second signal; a dataline driving unit connected to a plurality of data lines, and configuredto generate the display signal; and a timing control unit connected tothe common electrode driving unit, the gate driving unit and the dataline driving unit, wherein the timing control unit is configured to,during the display stage, control the gate driving unit to provide thedriving signal to the plurality of gate lines sequentially, control thedata line driving unit to provide the display signal to the data line,and control the common electrode driving unit to provide the commonvoltage signal to the common electrode; and wherein the timing controlunit is further configured to, during the touch sensing stage, controlthe common electrode driving unit to provide the first signal to thecommon electrode for realizing touch detection, and control the gatedriving unit to provide the second signal to the plurality of gatelines.
 10. The driving circuit according to claim 9, wherein the dataline driving unit is further configured to generate the third signal;and the timing control unit is further configured to control the dataline driving unit to provide the third signal to the plurality of datalines during the touch sensing stage.
 11. The driving circuit accordingto claim 8, comprising: a common electrode driving unit configured togenerate the common voltage signal and the first signal; a gate drivingunit connected to a plurality of gate lines, and configured to generatethe driving signal; a data line driving unit connected to a plurality ofdata lines, wherein the data line driving unit is configured to generatea display signal, and is further configured to generate the thirdsignal; and a timing control unit connected to the common electrodedriving unit, the gate driving unit and the data line driving unit,wherein the timing control unit is configured to, during the displaystage, control the gate driving unit to provide the driving signal tothe plurality of gate lines sequentially, control the data line drivingunit to provide the display signal to the data line, and control thecommon electrode driving unit to provide the common voltage signal tothe common electrode; and the timing control unit is further configuredto, during the touch sensing stage, control the common electrode drivingunit to provide the first signal to the common electrode for realizingtouch detection, and control the data line driving unit to provide thethird signal to the plurality of data lines.
 12. The driving circuitaccording to claim 7, wherein the first driving module is directlyconnected to the gate line; or the first driving module is connected tothe gate line in a capacitive coupling manner.
 13. A driving method fordriving a touch display apparatus, wherein the touch display apparatuscomprises: a first substrate; a second substrate arranged opposite tothe first substrate, wherein gate lines, data lines and thin filmtransistors are arranged on a surface of the second substrate facingtowards the first substrate; a liquid crystal layer arranged between thefirst substrate and the second substrate; and a common electrodearranged between the first substrate and the second substrate and usedas a touch sensing electrode during a touch sensing stage; wherein thedriving method comprises: providing a driving signal to the plurality ofgate lines sequentially, providing a display signal to the data line,and providing a common voltage signal to a plurality of electrode unitsof the common electrode, during a display stage; providing a firstsignal to the common electrode for realizing touch detection during thetouch sensing stage; providing a second signal to the gate line in theprocess of providing the first signal to the common electrode, whereinthe second signal is used to control the thin film transistor to beswitched off and is used to decrease charge and discharge capacity of acapacitor formed by the common electrode and the gate line; andproviding a third signal in the process of providing the first signal tothe common electrode, wherein the third signal is used to decreasecharge and discharge capacity of a capacitor formed by the commonelectrode and the data line, wherein the second signal is a pulse signalwith a same frequency and a same phase as the first signal, but has adifferent voltage level from the first signal, or the second signal is apulse signal with a same frequency, a same phase, and a same amplitudeas the first signal, but has a different voltage level from the firstsignal; wherein the driving circuit provides the third signal to thedata line, and the third signal is a pulse signal with a same frequency,a same phase, and a same voltage level as the first signal, or the thirdsignal is a pulse signal with a same frequency, a same phase, a samevoltage level, and a same amplitude as the first signal; and wherein thefirst signal, the second signal or the third signal is a square signal,a sine wave signal or a stair-step signal.